2,5-Diaziridinyl-3,6-bis(carboethoxyamino)-1,4-benzoquinone (AZQ: NSC-182986) is a new antitumor agent belonging to the chemical class of compounds known as aziridinylbenzoquinones. It shows a broad spectrum of antitumor activity in murine tumor sytems; in particular, it has been found to be active against P388, L1210 and ependymoblastoma when these tumors are inoculated intracranially. The objectives of this project are: (a) to study the disposition and metabolism of AZQ in rats and dogs; (b) to develop a suitable method for detecting and quantitating parent AZQ and its metabolites in biological fluids and tissues; and (c) to develop a tumor model system for testing AZQ and other potential antitumor agents that cross the blood-brain barrier.